Adjustable Ti2C3Alx-based segregated composite network for enhanced electromagnetic shielding and fire safety

With the rapid development of communication technology and portable electronic devices, the demand for the design of electronic devices with superior electromagnetic interference shielding and fire safety performance is increasing. Herein, epoxy resins (EPs) with typical segregated networks were designed by emulsion polymeri-zation and adhesion self-assembly strategies and novel polyphosphonitrile microspheres (PZS) synthesized by precipitation polymerization were used to improve the fire safety of EP composites. It is worth noting that the oil -water (EP to water) ratio in emulsion polymerization is closely related to the microscopic morphology of the segregated network. A smaller ratio of EP to water results in more paths for electrical charge transfer through the EP composites. As a result, EP/PT-3 with a minimum oil-to-water ratio exhibits a high EMI SE (electromagnetic interference shielding effectiveness) in the X-band ranging from 40.12 to 40.30 dB at a loading of 7.20 vol% Ti3C2Alx. Besides, the synergistic action of the adjustable Ti3C2Alx network with PZS endows EP superior flame retardant performance. Compared with EP, the PHRR and THR values of EP/PT-3 are down 55.7 % and 72.6 %, respectively. There is no doubt that EP/PT-3 has provided a new route for the preparation of Ti3C2Alx-based electromagnetic shielding and fireproof materials.